Septic tank vent screen

ABSTRACT

A retrofit mosquito screen cap attachment denies access to mosquitoes from entering a vent pipe connected to a subterranean septic or other fluid filled tank. It includes a mosquito screen pre-attached to a cap insertable over the one or more vertical open faces of the horizontal portion. The lower opening on the vertical downpipe is simply attached atop the open vent pipe. Preferably the pipe joint is made of PVC which is also the typical material of the vent pipe. A rigid PVC mosquito screening is used, which is bonded or sealed to the retrofit cap covering the pipe joint section. A robust material as opposed to a softer fabric screen is preferable to keep out bats or the beaks of birds attracted to hovering mosquitoes near the openings. The vertical orientation of the two vent holes helps keep debris from accumulating to clog the screened openings.

RELATED APPLICATIONS

This application is based upon provisional application Ser. No. 61/573,843 filed Sep. 13, 2011 and claims benefit and priority therefrom under 35 U.S.C. §119(e), which application is incorporated by reference herein. This application in part discloses and claims subject matter disclosed in my earlier filed patent application, Ser. No. 13/341,766, filed on Dec. 30, 2011, which application is incorporated by reference herein.

FIELD OF THE INVENTION

The present invention relates to mosquito control.

BACKGROUND OF THE INVENTION

Septic systems of buildings are vented to permit accumulated gasses to escape. Carbon dioxide and water vapor constitute some of the escaping gasses. However, mosquitoes are attracted to water vapor, as is commonly known, and to carbon dioxide, as noted in Pike; Jason, “Mosquito Host Attractants”, Colorado State University Entomology course, 2000. Methane is also present in septic systems.

It is well known that mosquitoes seek out still stagnant water to breed. In certain seasons the female is attracted to water vapor and carbon dioxide while seeking a hospitable place to lay eggs. Acting as a lure, septic system vent pipes create an entry to a perfect breeding ground, the septic tank. Besides increasing the local mosquito population, mosquitoes can also enter the living space of a house through any drain pipe with a dry trap or any break or hole in the vent pipe itself.

It is well to keep mosquitoes out of the septic tank or its attachments.

Individual or multiple septic tanks or vented cesspools which attract mosquitoes are not just used in residential homes, but also in commercial establishments, such as restaurants with or without rest rooms, gas stations with or without restrooms, or other commercial or industrial establishments, etc where humans inhabit, dwell or work and no direct sewage systems are routed to community wide underground municipal sewer systems. These septic systems or cesspools are vented to permit the escape of gasses, such as methane, carbon dioxide and/or water vapor.

Prior art proposals to place a screen at the top of the roof vent pipe of an underground septic tank are disclosed in a brochure of the Marin/Sonoma Mosquito & Vector Control District of Cotati, Calif. However, they allow rain to penetrate into the septic tank which can cause septic tank overflows. These vent pipes typically terminate a predetermined vertical distance feet above the ground and are open at the top so they are exposed to the falling particulate debris or weather elements, such as rain or snow, by being pointed upward.

OBJECTS OF THE INVENTION

It is therefore an object of the present invention to provide a mosquito control for preventing mosquitoes from breeding in septic tanks exposed to the air via waste gas and air vents which extend into the air above a subsurface septic tank or other water/liquid tank.

It is also an object of the present invention to provide an effective mosquito control by reducing exposed areas of still water used by mosquitoes for breeding, which utilizes existing waste gas and air vents and which promotes mosquito population control.

It is also an object of the present invention to prevent entry of particulate debris, rain or snow and resultant septic tank overflows.

Other objects which become apparent from the following description of the present invention.

SUMMARY OF THE INVENTION

The present invention provides a mosquito screen attachment to deny mosquitoes an entry to a vent pipe for a septic tank or cesspool that is both inexpensive and easy to install. To prevent rainfall from entering and clogging the systems, in one embodiment, it is in the form of a pipe T joint section with a sideways exposed mosquito screen pre-attached to the two vertical open faces of the horizontal portion. The third central opening on the vertical downpipe is simply attached atop the open vent pipe. Alternately, it can have other configurations of the pipe joint. For example, the pipe joint can be a J, X or L shape with a one or more sideways joints with vertically extending screened open faces.

In the preferred embodiment, the T section is made of injection molding process polyvinyl chloride pipe (PVC), which is also the typical material of the vent pipe. If the vent pipe is also PVC, commonly available PVC cement can be used to attach the vent to the end of the vent pipe. If other materials are used, adhesive sealants can be used for installation. Typically, the vent pipe is a standard size such as a “Schedule 40” two-inch diameter pipe. In any case, the T section of the vent would be appropriately sized to match the vent pipe end. The same is true for other configurations of the pipe joint, such as those having J, X or L shapes or other geometric shapes wherein one or more sideways open faces are screened in but the tops thereof are covered, to keep falling particulate debris, rain or snow from entering from above.

The screen can be made of metal or plastic. The process to attach the screen can be by bonding, mechanical attachment, or gluing. It can also be installed during the molding process.

In the preferred embodiment, a rigid PVC mosquito screening is used. This can be bonded to the edges of the two vertical holes at either end of the horizontal section of the T using PVC cement. Alternatively, metal screening such as aluminum or copper can be attached using an adhesive sealant or by mechanical attachments, such as with screws and gaskets. A robust material as opposed to a softer fabric screen is preferable to keep out bats or the beaks of birds attracted to hovering mosquitoes near the openings. The sideways exposed vertical orientation of the two vent holes helps keep particulate debris, rain or snow from accumulating to clog the screened openings. One or more screened openings, each equal to the diameter of the original vent pipe, are used to negate any reduction in the effective vent area of the original unobstructed vent pipe.

In an alternate embodiment, a retrofit cap is retrofitted with a screen, where the retrofit cap provides a tight fit on the pipe section.

The retrofit cap has an outer diameter and an inner diameter The inner diameter of the retrofit cap is slightly larger than the outer diameter of the pipe section stem, with a little leeway for either an adhesive material, such as cement or glue, or else a form fitting gasket of compressible elastomeric material, to provide a tight fit of the retrofit cap on the pipe section.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention can best be understood in connection with the accompanying drawings. It is noted that the invention is not limited to the precise embodiments shown in drawings, in which:

FIG. 1 is a perspective view of a non vented prior art pipe end with mosquitoes entering and leaving;

FIG. 1A is a perspective view of an open topped prior art pipe end with a screen to prevent mosquitoes entering and leaving through the top opening exposed to fine particle debris or weather elements, such as rain or snow falling from above and directly down into the pipe.

FIG. 2 is a perspective view of a preferred embodiment of the septic system vent screen attachment of the present invention.

FIG. 3 is a perspective view of an alternate embodiment of the septic system vent screen attachment of the present invention with a horizontally oriented L-shaped configuration having two vertically extending screened vent openings.

FIG. 4 is a perspective view of an alternate embodiment of the septic system vent screen attachment of the present invention with a vertically oriented X-shaped configuration having one vertically extending screened vent opening.

FIG. 5 is a perspective view of an alternate embodiment of the septic system vent screen attachment of the present invention with a horizontally extending J-shaped configuration having four vertically extending screened vent openings.

FIGS. 6, 6A, 6B and 6C show an alternate embodiment for a retrofit cap, wherein:

FIG. 6 is an exploded perspective view of a pipe section and a retrofit cap having a mosquito screen on an exterior end thereof;

FIG. 6A is a crossectional view thereof, taken along view line “6A-6A” of FIG. 6B, of the cap installed on a pipe section;

FIG. 6B is a right side elevation view thereof; and,

FIG. 6C is a front elevational view thereof.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 shows the prior art situation with a vent pipe 1 having an open end through which mosquitoes can enter and leave at will.

FIG. 1A shows another prior art vent pipe la having a screened horizontally oriented top open end through which debris, rain and snow can enter and clog the septic tank or other waste disposal structure within the ground.

FIG. 2 shows the vent pipe screen attachment 2 as a pipe T joint with horizontal section 6 and downpipe 4. Note that downpipe 4 is attached to the open end of vent pipe 1. Circular screen sections 8 are adhesively attached to the open ends of horizontal section 6 by using adhesive in the edge ring area 10.

FIG. 3 shows the vent pipe screen attachment 20 as a pipe having a horizontally oriented L-shaped joint with two horizontal sections 26 and downpipe 24, which is attached to the open end of the vent pipe 21. Circular screen sections 28 are adhesively attached to the open ends of horizontal section 26 by using adhesive or other attachment means in the edge ring area 29.

FIG. 4 shows the vent pipe screen attachment 40 as a vertically oriented shaped pipe (X shape) joint with four horizontal sections 46 and downpipe 44, which is attached to the open end of a vent pipe 41. Circular screen sections 48 are adhesively attached to the open ends of horizontal section 46 by using adhesive or other attachment means in the edge ring area 49.

FIG. 5 shows the vent pipe screen attachment 30 as a joint-shaped pipe joint (J shape) with one horizontal section 36 and downpipe 34 attached to the open end of a vent pipe 31. Circular screen section 38 is adhesively attached to the open ends of horizontal section 36 by using adhesive or other attachment means in the edge ring area 39.

While FIGS. 2-5 respectively show pipe joints having T-shaped, L-shaped, X-shaped or J-shaped configurations with one or more vertically extending screened vent openings, it is assumed that any geometric configuration may be used, so long as the opening is shielded from above from weather elements, to prevent rain and snow from entering and clogging the septic tanks or other waste disposal structures.

FIGS. 6, 6A, 6B and 6C show an alternate embodiment for a retrofit cap with a mosquito screen 228 on an exterior side thereof, where the screen 228 is on the retrofit cap 220 itself, not on the pipe section. The cap 220 has an outer diameter “OD” and an inner diameter “ID” separated by an annular peripheral face portion 226. The inner diameter ID of the cap 220 is slightly larger than the outer diameter of the pipe section stem 200, with a little leeway for the applied thickness of an adhesive material, such as glue or cement, to connect the cap and screen 220 to the pipe section 200, or else a form fitting gasket of compressible elastomeric material 229, to provide a tight fit of the cap on a forward distal portion 206 of the pipe section 200.

The screen of FIGS. 6, 6A, 6B and 6C can be made of metal or plastic. The process to attach the screen can be by bonding, mechanical attachment, or gluing. It can also be installed during the molding process.

There are several options for the size of the caps. To fit over a 55 mm pipe T-section elbowed pipe, the outer diameter (OD)of the cap is about 59 mm and the inner diameter (ID) is about 55 mm, with a 5 mm clearance for adhesive and/or a gasket. Suitable for the 40 mm diameter pipe T section elbowed pipe is a retrofit cap having an outer diameter (OD) of about 49 mm and an inner diameter (ID) of about 45 mm, with about a 5 mm clearance for adhesive and/or a gasket.

For either the 40 mm pipe retrofit cap or the 50 mm pipe retrofit cap, the forward length is about 25 mm. Although other grid patterns may be used for the screen, preferably the mesh hole is a round shape with a hole diameter of about 1 mm, and where the distance between two holes is about 5 mm.

In this alternate embodiment of FIGS. 6, 6A, 6B and 6C, a rigid PVC mosquito screening material for screen 228 is also used. Screen 228 can be bonded to the distal edges of the cap 220 using PVC cement. Alternatively, metal screening such as aluminum or copper can be attached to the cap 220 using an adhesive sealant or by mechanical attachments, such as with screws and gaskets.

In the foregoing description, certain terms and visual depictions are used to illustrate the preferred embodiment. However, no unnecessary limitations are to be construed by the terms used or illustrations depicted, beyond what is shown in the prior art, since the tennis and illustrations are exemplary only, and are not meant to limit the scope of the present invention.

It is further known that other modifications may be made to the present invention, without departing the scope of the invention. 

1. A retrofit mosquito screen cap attachment which denies access to mosquitoes from entering a vent pipe connected to a subterranean septic or other fluid filled tank comprising: at least one pipe joint section having at least one sideways oriented, vertically extending open face of a horizontally extending pipe portion, said sideways oriented, vertically extending open face having a retrofit cap with a mosquito screen attached thereto, said at least one mosquito screen of said cap covering said sideways oriented, vertically extending open face to prevent mosquitoes from entering said at least one pipe joint section, wherein said at least one sideways oriented, vertically extending open face is screened in, and, said at least one pipe joint section having a covered top roof portion to keep falling particulate debris, rain or snow from entering from above; said at least one pipe joint section having a lower opening on a vertical downpipe section attached atop the open vent pipe connected to the subterranean septic or other fluid filled tank.
 2. The retrofit mosquito screen cap attachment as in claim 1 wherein said at least one pipe joint section is a pipe T joint with a horizontal section and a vertical downpipe attached to said open end of said vent pipe connected to the subterranean septic or other fluid filled tank.
 3. The retrofit mosquito screen cap attachment as in claim 1 wherein said at least one pipe joint section includes a horizontally oriented L-shaped joint with two horizontally extending sections and a vertical downpipe attached to the open end of the vent pipe connected to the subterranean septic or other fluid filled tank.
 4. The retrofit mosquito screen cap attachment as in claim 1 wherein said at least one pipe joint section comprises a vertically oriented J-shaped pipe joint with one horizontal section and a vertical downpipe attached to the open end of said vent pipe connected to the subterranean septic or other fluid filled tank.
 5. The retrofit mosquito screen cap attachment as in claim 1 wherein said at least one pipe joint section is a multi joint X-shaped pipe joint with four horizontal section and a vertical downpipe attached to the open end of the vent pipe connected to the subterranean septic or other fluid filled tank.
 6. The retrofit mosquito screen cap attachment as in claim 1 wherein said pipe joint and said cap are made of polyvinyl chloride PVC piping material.
 7. The retrofit mosquito screen cap attachment as in claim 6 wherein said PVC piping section and said retrofit cap are separately injection molded.
 8. The retrofit mosquito screen cap attachment as in claim 6 wherein said mosquito screen is attached to said retrofit cap by PVC cement.
 9. The retrofit mosquito screen cap attachment as in claim 6 wherein said mosquito screen is attached to said retrofit cap by an adhesive sealant.
 10. The retrofit mosquito screen cap attachment as in claim 6 wherein said mosquito screen is bonded to a respective front annular peripheral edge of said retrofit cap.
 11. The retrofit mosquito screen cap attachment as in claim 6 wherein said mosquito screen is attached to said retrofit cap by glue.
 12. The retrofit mosquito screen cap attachment as in claim 6 wherein said mosquito screen is a robust metal screen.
 13. The retrofit mosquito screen cap attachment as in claim 6 wherein said mosquito screen is a robust plastic screen.
 14. The retrofit mosquito screen cap attachment as in claim 6 wherein said mosquito screen is molded together with said retrofit cap.
 15. The retrofit mosquito screen cap attachment as in claim 6 wherein said mosquito screen is attached to said retrofit cap by mechanical attachments.
 16. The retrofit mosquito screen cap attachment as in claim 1 wherein said at least one pipe joint section is a plurality of pipe joint sections, each with a respective sideways oriented, vertically extending open face covered by said at least one respective mosquito screen, each pipe section covered by a separate retrofit cap.
 17. The retrofit mosquito screen cap attachment as in claim 10 wherein said retrofit cap has an outer diameter and an inner diameter separated by an annular peripheral face portion, said inner diameter of said retrofit cap being larger than an outer diameter of said pipe section to connect said retrofit cap and screen to the pipe section.
 18. The retrofit mosquito screen cap attachment as in claim 17 further comprising a form fitting gasket of compressible elastomeric material providing a tight fit of said retrofit cap on said forward distal portion of said pipe section. 